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Hantavirus Cardiopulmonary Syndrome (HCPS) is a disease caused by Hantavirus, which is highly virulent for humans. High temperatures and conversion of native vegetation to agriculture, particularly sugarcane cultivation can alter abundance of rodent generalist species that serve as the principal reservoir host for HCPS, but our understanding of the compound effects of land use and climate on HCPS incidence remains limited, particularly in tropical regions. Here we rely on a Bayesian model to fill this research gap and to predict the effects of sugarcane expansion and expected changes in temperature on Hantavirus infection risk in the state of São Paulo, Brazil. The sugarcane expansion scenario was based on historical data between 2000 and 2010 combined with an agro-environment zoning guideline for the sugar and ethanol industry. Future evolution of temperature anomalies was derived using 32 general circulation models from scenarios RCP4.5 and RCP8.5 (Representative greenhouse gases Concentration Pathways adopted by IPCC). Currently, the state of São Paulo has an average Hantavirus risk of 1.3%, with 6% of the 645 municipalities of the state being classified as high risk (HCPS risk ≥ 5%). Our results indicate that sugarcane expansion alone will increase average HCPS risk to 1.5%, placing 20% more people at HCPS risk. Temperature anomalies alone increase HCPS risk even more (1.6% for RCP4.5 and 1.7%, for RCP8.5), and place 31% and 34% more people at risk. Combined sugarcane and temperature increases led to the same predictions as scenarios that only included temperature. Our results demonstrate that climate change effects are likely to be more severe than those from sugarcane expansion. Forecasting disease is critical for the timely and efficient planning of operational control programs that can address the expected effects of sugarcane expansion and climate change on HCPS infection risk. The predicted spatial location of HCPS infection risks obtained here can be used to prioritize management actions and develop educational campaigns., Author summary Hantavirus, hosted by rodent species, causes HCPS, a disease with a 50% mortality rate in humans. The conversion of native vegetation to sugarcane increases the abundance of hantavirus reservoir rodent species, augmenting disease risk. Additionally, temperature also has positive effects on disease risk because it affects rodent population and the time the virus remains infectious in the environment. Here we evaluate the impacts of climate change and sugarcane expansion on HCPS risk. Expansion of sugarcane increases average HCPS risk placing 20% more people at risk for acquiring HCPS than under current conditions. Temperature anomalies increase HCPS risk even more and place 31% and 34% more people at risk (RCP4.5 and RCP8.5, respectively). Our results confirm the impacts of climate change and agriculture expansion on disease risk and highlight the need for timely and efficient planning of operational control programs in order to avoid disease propagation in the future.

ilustraciones, gráficas, tablas La friabilidad es una propiedad dinámica y determinante en la respuesta físico-mecánica del suelo a la labranza y resulta esencial en la obtención de una adecuada cama de siembra para los cultivos. Su comportamiento se ha asociado a la naturaleza de otras propiedades edáficas y al contenido de agua, por lo tanto, requiere ser estudiada de manera integral con las diferentes propiedades físicas, químicas y mineralógicas del suelo. En Colombia no se han reportado estudios que evalúen cuantitativamente la friabilidad de los suelos, por lo que el presente trabajo constituye un estudio piloto en este tópico. El objetivo general de esta investigación fue evaluar la influencia de la mineralogía de la fracción arcilla y otras propiedades edáficas en la friabilidad de suelos cultivados en caña de azúcar. Por su parte, los objetivos específicos fueron i) determinar el efecto del tamaño de los agregados y la diferenciación de los horizontes superficiales en el índice de friabilidad de los suelos, usando el coeficiente de variación multivariante, ii) evaluar el efecto del dominio de los minerales arcillosos tipo 1: 1 (caolinitas) y 2:1 (esmectitas y vermiculitas), la textura y el contenido de carbono orgánico en el índice de friabilidad de los suelos, iii) evaluar la relación de la friabilidad con diferentes propiedades físicas y químicas de los suelos, y iv) Evaluar el contenido de agua en el que suelos cultivados en caña de azúcar adquieren su condición de óptima (máxima) friabilidad y su relación con el límite plástico. Se destaca que el estudio se llevó a cabo en 18 fincas localizadas en el centro y sur del departamento del Valle del Cauca y norte del departamento del Cauca (Colombia), realizando muestreos de suelos en los dos primeros horizontes (Ap y A1) de 91 sitios de observación. Se estimó el índice de friabilidad (IF) a 9840 agregados recolectados, utilizando el método de resistencia al rompimiento; los agregados fueron obtenidos de 182 bloques de suelo, posteriormente secados en invernadero y en horno a baja temperatura (40°C), segregados en cuatro tamaños y finalmente sometidos a compresión para determinar su resistencia al rompimiento. Este importante volumen de muestras fue un aspecto fundamental para la confiabilidad de los resultados encontrados. Los horizontes del perfil de suelo se caracterizaron en campo según la descripción morfológica y en el laboratorio se determinaron las propiedades: físicas (densidad aparente, textura, límites de Atterberg, diámetro ponderado medio de los agregados, estado de agregación y los contenidos de agua de los agregados a diferentes potenciales de presión: -10, -30, -100 y -300 kPa); químicas (carbono orgánico, pH y conductividad eléctrica) y mineralógicas (tipos de arcillas). El análisis estadístico se realizó a partir de un enfoque descriptivo e inferencial usando métodos univariantes y multivariantes. El estudio mostró variación del IF con el tamaño de los agregados y horizontes superficiales, y un valor más conveniente del mismo utilizando el coeficiente de variación multivariante, a partir del cual se estimó el límite inferior del coeficiente de variación (IFi) como el valor más representativo del IF; de otro lado, no se encontró efecto con nivel de significancia del diámetro ponderado medio de los agregados estables al agua, de la densidad aparente, del pH ni de la conductividad eléctrica en el IFi. No obstante, el estado de agregación y la porosidad total del suelo mostraron efecto significativo en el IFi. En este trabajo no se encontró efecto significativo de la dominancia de arcillas 1:1 y 2:1 cuando la variable respuesta fue el IFi, pero si una tendencia (desde el punto de vista descriptivo) a presentar mayor IFi los suelos con dominio de arcillas 1:1; por el contrario, la fracción de arena total del suelo y el contenido de carbono orgánico (CO) presentaron efecto altamente significativo, encontrando que los suelos fueron más friables con los mayores contenidos de CO y los menores contenidos de la fracción de arena total. Mediante modelo estadístico-matemático se estimó la máxima friabilidad en el horizonte Ap de los suelos en un valor del IFi de 0.498 y en el horizonte A1 en un valor del IFi de 0.410; estos valores de máxima friabilidad se asociaron a contenidos de agua de 332.04 y 279.89 g kg-1 respectivamente y se correspondieron con potenciales de presión de -78.62 y -30.08 kPa. A partir de análisis de correlación canónica que incluyeron las variables: IFi, potenciales de presión (T), retención de agua (RA) y contenido de agua obtenido experimentalmente en el LP, se generó un modelo estadístico que permitió estimar el contenido de agua en el LP (ALP) para los suelos en su condición de máxima (óptima) friabilidad, tanto en Ap como en A1. Se encontró que el contenido de agua en el que se obtuvo la máxima (óptima) friabilidad fue muy cercano (por debajo) a aquel donde los suelos adquirieron el límite plástico (estimado por modelo); este contenido de agua en el que se obtuvo la máxima friabilidad estuvo en el rango entre 0.88*ALP (horizonte Ap) y 0.91*ALP (horizonte A1). De otra parte, se encontró que el IFi fue mayor en algunos suelos en los que se encontró desarrollo de microestructura (bloques subangulares) en relación con aquellos que carecieron de la misma (masiva), confirmando la relación positiva entre desarrollo de microestructura y el IFi. Los resultados de esta investigación constituyen información inédita en el país, encaminada a mejorar la sostenibilidad de la producción agrícola y evitar el deterioro de la calidad del suelo a partir del conocimiento de la friabilidad y su relación con diferentes propiedades del suelo. Este propósito obedece a la necesidad de lograr la reducción del gasto de energía, consumo de combustible y emisión de gases efecto invernadero (GEI) asociados a las operaciones de labranza. (Texto tomado de la fuente). Friability is a dynamic property that is determinant for the physical‐mechanical response of soils for tillage and, therefore, is essential for creating a suitable medium for crops. Its behavior has been associated with the nature of other soil properties and moisture content; therefore, it needs to be studied in an integrated way with different physical, chemical, and mineralogical properties of soils. In Colombia, no studies have quantitatively evaluated the friability of soils, which is why the present study established a pilot study for this topic. The general objective of this research was to evaluate the influence of the mineralogy of the clay fraction and other soil properties on the friability of soils cultivated with sugar cane. The specific objectives included i) determining the effect of the size of the aggregates and differentiation of the superficial horizons on the friability index of the soils using the multivariate coefficient of variation, ii) evaluating the effect from the predominance of clay mineral types 1:1 and 2:1, texture, and organic carbon content on the soil friability index, iii) evaluating the relationship between the friability and different physical and chemical properties of the soils, and iv) evaluating the soil water content at which the soils cultivated with sugar cane obtained the optimal conditions (maximum) of friability and its relationship with the plastic limit. This studied was carried out on 18 farms located in the central and southern regions of the Valle del Cauca Department and in the northern region of the Cauca Department (Colombia), taking soil samples of the first two horizons (Ap and A1) at 91 observation sites. Friability index (FI) was estimated for 9840 collected aggregates using the tensile strength method. The aggregates were obtained from 182 soil blocks, which were dried in a greenhouse and lowtemperature oven (40°C), separated into four sizes and, finally, subjected to compression to determine their tensile strength. This significant sample volume was fundamental to the reliability of the results. The horizons of the soil profile were characterized in the field according to the morphological description, and the following properties were determined: physical (bulk density, texture, Atterberg limit, the mean weight diameter of aggregates, aggregation state, and water content of the aggregates at different matric potentials: ‐10, ‐30, ‐100 and ‐300 kPa); chemical (organic carbon, pH, and electric conductivity) and mineralogical (clay type). The statistical analysis was carried out with a inferential and descriptive focus using multivariate and univariate methods. This study showed an FI variation related to the size of the aggregates and the surface horizons and a more relevant FI value using the multivariate coefficient of variation, from which the lower limit of the coefficient of variation (FIi) was estimated as the most representative value of the FI. On the other hand, the mean weight diameter of the aggregates, the bulk density, the pH, and the electric conductivity did not have an effect at a significant level on the FIi. Nevertheless, the aggregation state and the total porosity of the soils demonstrated a significant effect on the FIi. This study did not show a significant effect from the 1:1 and 2:1 clay predominance when the response variable was the FIi, but there was a tendency (from the descriptive point of view) to show a higher FIi in the soils with a 1:1 clay predominance. However, the total sand fraction of the soil and organic carbon (OC) content show highly significant effects, with soils that were friable with the higher OC contents and lower contents for the total sand fraction. A statistical‐mathematical model was used to estimate the maximum friability of the Ap horizon at a FIi value of 0.498 and at a FIi value of 0.410 for the A1 horizon. These maximum friability values were associated with water contents of 332.04 and 279.89 g kg‐1, respectively, and corresponded to matric potentials of ‐78.62 and ‐30.08 kPa, respectively. A statistical model was generated from the canonical correlation analysis, which included the varibles FIi, matric potential (P), water retention (WR) and water content experimentally obtained in the PL, that facilitated an estimation of the water content in the PL (MPL) of the soils at thier maximum (optimal) friability for both Ap and A1. The results showed that the water content that resulted in the maximum (optimal) friability was very close (below) to the moisture their content that resulted in the plastic limit of the soils(as estimated by the model); the water content from which the maximum friability was obtained demonstrated a range of 0.88* MPL (Ap horizon) to 0.91* MPL (A1 horizon). Finally, the FIi was higher in some soils that had microstructural development (subangular blocky) than in soils that lacked them (massive), confirming the positive relationship between microstructural development and the FIi. This study provided unpublished information for the country, aimed at improving sustainability for agricultural production and avoiding the deterioration of soil quality with knowledge on friability and its relationship with different soil properties; goals that are rooted in the need to reduce the energy use, consumption of combustibles, and emissions of greenhouse gases (GHG) that are associated with farming operations. Incluye anexos Doctorado Doctor en Ciencias Agrarias Suelos y aguas Ciencias Agronómicas

Made available in DSpace on 2014-06-11T19:29:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-01Bitstream added on 2014-06-13T20:39:12Z : No. of bitstreams: 1 fernandesjunior_ar_me_ilha.pdf: 353041 bytes, checksum: 24615fb9c4cb2e7357d03d6db98b28cc (MD5) A interação genótipos com ambientes (GxA) representa uma das principais dificuldades para a seleção nos programas de melhoramento genético de qualquer espécie, seja na fase de seleção ou na recomendação de cultivares, onde os pesquisadores buscam alternativas para minimizar seus efeitos. Entre as alternativas está a escolha de cultivares com ampla adaptação e boa estabilidade. Os resultados de vários ambientes podem ser sintetizados por estudos de adaptabilidade e estabilidade fenotípica, permitindo conhecer melhor a capacidade produtiva e adaptação frente às variações ambientais de novos genótipos. O objetivo deste trabalho foi verificar a adaptabilidade e estabilidade de clones de cana-de- açúcar, além da estabilidade dos ambientes, quanto à produtividade em toneladas de colmos por ha (TCH) e toneladas de pol por ha (TPH) no Estado de São Paulo. Foram avaliados 10 clones e duas testemunhas comerciais de maturação média- tardia em primeira soca em 10 experimentos colhidos em agosto de 2008, utilizando o método de regressão bissegmentada e o método AMMI (Additive Main Effects and Multiplicative Interaction Analysis). A interação GxA para o caráter Pol%cana (PC) não foi significativa e TCH e TPH foram altamente correlacionados (r=0,97), apresentando resultados similares para todas as análises realizadas. Por isso, apenas os resultados de TCH foram apresentados e discutidos. Os resultados dos dois métodos foram comparados e evidenciaram que os clones RB975201, RB975157, RB975932, RB975242 e RB975162 são os mais promissores devido à produtividade acima das testemunhas, a alta estabilidade verificada em um ou nos dois métodos e adaptabilidade ampla ou específica. Os ambientes Tarumã, Guariba e Piracicaba, foram os mais estáveis, podendo servir de referência para recomendações em outras áreas The genotype x environment interaction (GE) is one of the main difficulties for selection in breeding programs of any species, either at the stage of selection or recommendation of cultivars, where researchers seek alternatives to minimize their effects. Between the alternatives is the choice of cultivars with wide adaptability and good stability. The results of various environments can be synthesized by studies of phenotypic adaptability and stability allowing better understand the production capacity and adaptation to environmental variations ahead of new genotypes. The objective of this study was to verify the adaptability and stability of sugar cane clones, in addition the stability of environments, for productivity in tons of cane per hectare (TCH) and tons pol per hectare (TPH) in São Paulo State, Brazil. Were evaluated 10 clones and two commercial checks of medium-late maturation in first-ratoon of experiments harvested in August 2008, utilizing bissegmented regression method and analysis AMMI (Additive Main Effects and Multiplicative Interaction Analysis). The interaction for the character Pol%cane (PC) was not significant and TCH and TPH were highly correlated (r = 0.97), with similar results for all analyzes. Therefore, only the results of TCH were presented and discussed. The results of two methods were compared and evidenced that clones RB975201, RB975157, RB975932, RB975242 and RB975162 are the most promising due to yield above checks, high stability observed in one or both methods and broad or specific adaptability. The environments Tarumã, Guariba and Piracicaba, are the most stable and may use as reference for recommendations in other areas

Thesis (PhD)--University of South Australia, 2001. Includes bibliographical references (pages 302-327) The competitiveness of the Australian sugar industry (briefly presented in chapter 2) in an international market context, frequently distorted by protectionism, is without doubt, also the consequence of its ability to implement the results of the research funded by the sugar industry. The present project, which addresses the problems of road sugar cane transport from the producers to the processing unit (mill), is also integrated in the same research area.